user
Explain the concept of "opportunity cost".


assistant
Opportunity cost is the cost of an opportunity not taken; it is the cost of the next best alternative. It is the value of the forgone alternatives when one alternative is chosen. Opportunity cost reflects the full economic cost of a decision, and can be seen as the true cost of a choice. For example, if someone chooses to spend money on a vacation, the opportunity cost of that decision are the other things that money could have been spent on.